Manuel de Miguel

NLRP3 inflammasome is activated in mononuclear blood cells from patients with major depressive disorder

INTRODUCTION Major depressive disorder (MDD) is a very prevalent disease which pathogenic mechanism remains elusive. There are some hypotheses and pilot studies suggesting that cytokines may play an important role in MDD. In this respect, we have investigated the role of NLRP3 inflammasome complex in the maturation of caspase-1 and the processing of its substrates, IL-1β and IL-18, in blood cells from MDD patients. METHODS Forty MDD patients were selected for this study, twenty without treatments and twenty treated with amitriptyline, a common tricyclic antidepressant. Blood samples from twenty healthy volunteers were included in the study. The inflammasome activation was studied by Western blot and real-time PCR of NLRP3 and caspase 1 and serum levels of IL-1β and 18. RESULTS We observed increased gene expression of NLRP3 and caspase-1 in blood cells, and increased serum levels of IL-1β and IL-18 in non-treated patients. IL-1β and IL-18 correlated with Beck Depression Inventory (BDI) scores of MDD patients. Interestingly, amitriptyline treatment reduced NLRP3 and caspase-1 gene expression, and IL-1β and IL-18 serum levels. As it is well established that oxidative stress is associated with NLRP3 inflammasome activation, we next studied mitochondrial ROS and lipid peroxidation (LPO) levels in MDD patients. Increased levels of mitochondrial ROS and LPO were observed in MDD patients, however oxidative damage was higher in MDD patients treated with amitriptyline. CONCLUSIONS These findings provide new insight into the pathogenesis of MDD and the effects of amitriptyline treatment on NLRP3 inflammasome activation and IL-1β and IL-18 serum levels.

Mitochondrial dysfunction and mitophagy activation in blood mononuclear cells of fibromyalgia patients: implications in the pathogenesis of the disease

IntroductionFibromyalgia is a chronic pain syndrome with unknown etiology. Recent studies have shown some evidence demonstrating that oxidative stress may have a role in the pathophysiology of fibromyalgia. However, it is still not clear whether oxidative stress is the cause or the effect of the abnormalities documented in fibromyalgia. Furthermore, the role of mitochondria in the redox imbalance reported in fibromyalgia also is controversial. We undertook this study to investigate the role of mitochondrial dysfunction, oxidative stress, and mitophagy in fibromyalgia.MethodsWe studied 20 patients (2 male, 18 female patients) from the database of the Sevillian Fibromyalgia Association and 10 healthy controls. We evaluated mitochondrial function in blood mononuclear cells from fibromyalgia patients measuring, coenzyme Q10 levels with high-performance liquid chromatography (HPLC), and mitochondrial membrane potential with flow cytometry. Oxidative stress was determined by measuring mitochondrial superoxide production with MitoSOX™ and lipid peroxidation in blood mononuclear cells and plasma from fibromyalgia patients. Autophagy activation was evaluated by quantifying the fluorescence intensity of LysoTracker™ Red staining of blood mononuclear cells. Mitophagy was confirmed by measuring citrate synthase activity and electron microscopy examination of blood mononuclear cells.ResultsWe found reduced levels of coenzyme Q10, decreased mitochondrial membrane potential, increased levels of mitochondrial superoxide in blood mononuclear cells, and increased levels of lipid peroxidation in both blood mononuclear cells and plasma from fibromyalgia patients. Mitochondrial dysfunction was also associated with increased expression of autophagic genes and the elimination of dysfunctional mitochondria with mitophagy.ConclusionsThese findings may support the role of oxidative stress and mitophagy in the pathophysiology of fibromyalgia.

Secondary coenzyme Q10 deficiency triggers mitochondria degradation by mitophagy in MELAS fibroblasts

Mitochondrial encephalomyopathy, lactic acidosis, and stroke‐like episodes (MELAS) is a mitochondrial disease most usually caused by point mutations in tRNA genes encoded by mtDNA. Here, we report on how this mutation affects mitochondrial function in primary fibroblast cultures established from 2 patients with MELAS who harbored the A3243G mutation. Both mitochondrial respiratory chain enzyme activities and coenzyme Q10 (CoQ) levels were significantly decreased in MELAS fibroblasts. A similar decrease in mitochondrial membrane potential was found in intact MELAS fibroblasts. Mitochondrial dysfunction was associated with increased oxidative stress and the activation of mitochondrial permeability transition (MPT), which triggered the degradation of impaired mitochondria. Furthermore, we found defective autophagosome elimination in MELAS fibroblasts. Electron and fluorescence microscopy studies confirmed a massive degradation of mitochondria and accumulation of autophagosomes, suggesting mitophagy activation and deficient autophagic flux. Transmitochondrial cybrids harboring the A3243G mutation also showed CoQ deficiency and increased autophagy activity. All these abnormalities were partially restored by CoQ supplementation. Autophagy in MELAS fibroblasts was also abolished by treatment with antioxidants or cyclosporine, suggesting that both reactive oxygen species and MPT participate in this process. Furthermore, prevention of autophagy in MELAS fibroblasts resulted in apoptotic cell death, suggesting a protective role of autophagy in MELAS fibroblasts.—Cotán, D., Cordero, M. D., Garrido‐Maraver, J., Oropesa‐Ávila, M., Rodríguez‐Hernández, A., Gómez Izquierdo, L., De la Mata, M., De Miguel, M., Bautista Lorite, J., Rivas Infante, E., Jackson, S., Navas, P., Sánchez‐Alcázar, J. A. Secondary coenzyme Q10 deficiency triggers mitochondria degradation by mitophagy in MELAS fibroblasts. FASEB J. 25, 2669–2687 (2011). www.fasebj.org

Clonality as Expression of Distinctive Cell Kinetics Patterns in Nodular Hyperplasias and Adenomas of the Adrenal Cortex

Although histopathologic criteria for adrenal cortical nodular hyperplasias (ACNHs) and adenomas (ACAs) have been developed, their kinetics and clonality are virtually unknown. We studied 20 ACNHs and 25 ACAs (based on World Health Organization criteria) from 45 females. Representative samples were histologically evaluated, and the methylation pattern of the androgen receptor alleles was analyzed on microdissected samples. Consecutive sections were selected for slide cytometry, flow cytometry, and in situ end labeling (ISEL). Apoptosis was studied by flow cytometry (nuclear area/DNA content plotter analysis) and by ISEL. Appropriate tissue controls were run in every case. Polyclonal gel patterns were revealed in 14/18 informative ACNHs and in 3/22 informative ACAs, whereas monoclonal gel patterns were observed in 4/18 ACNHs and 19/22 ACAs. Overlapping proliferation rates (PRs) were observed in both clonal groups, and apoptosis was detected only in G(0)/G(1) cells, especially in monoclonal ACNHs (3/4; 75%) and in polyclonal ACAs (2/3; 67%). Significantly higher PRs were observed in ACNHs with polyclonal patterns and G(0)/G(1) apoptosis and in ACAs regardless of clonality pattern and presence of G(0)/G(1) apoptosis. All except one ACNH (19/20; 95%) and 15/25 ACAs (60%) showed diploid DNA content, whereas the remaining cases were hyperdiploid. A direct correlation between PR and ISEL was observed in polyclonal lesions (PR = 29.32 ISEL - 1.93), whereas the correlation was inverse for monoclonal lesions (PR = -9.13 ISEL + 21.57). We concluded that only simultaneous down-regulated apoptosis and high proliferation result in selective kinetic advantage, dominant clone expansion, and unbalanced methylation patterns of androgen receptor alleles in ACNHs and ACAs.

Autophagy in periodontitis patients and gingival fibroblasts: unraveling the link between chronic diseases and inflammation

BackgroundPeriodontitis, the most prevalent chronic inflammatory disease, has been related to cardiovascular diseases. Autophagy provides a mechanism for the turnover of cellular organelles and proteins through a lysosome-dependent degradation pathway. The aim of this research was to study the role of autophagy in peripheral blood mononuclear cells from patients with periodontitis and gingival fibroblasts treated with a lipopolysaccharide of Porphyromonas gingivalis. Autophagy-dependent mechanisms have been proposed in the pathogenesis of inflammatory disorders and in other diseases related to periodontitis, such as cardiovascular disease and diabetes. Thus it is important to study the role of autophagy in the pathophysiology of periodontitis.MethodsPeripheral blood mononuclear cells from patients with periodontitis (n = 38) and without periodontitis (n = 20) were used to study autophagy. To investigate the mechanism of autophagy, we evaluated the influence of a lipopolysaccharide from P. gingivalis in human gingival fibroblasts, and autophagy was monitored morphologically and biochemically. Autophagosomes were observed by immunofluorescence and electron microscopy.ResultsWe found increased levels of autophagy gene expression and high levels of mitochondrial reactive oxygen species production in peripheral blood mononuclear cells from patients with periodontitis compared with controls. A significantly positive correlation between both was observed. In human gingival fibroblasts treated with lipopolysaccharide from P. gingivalis, there was an increase of protein and transcript of autophagy-related protein 12 (ATG12) and microtubule-associated protein 1 light chain 3 alpha LC3. A reduction of mitochondrial reactive oxygen species induced a decrease in autophagy whereas inhibition of autophagy in infected cells increased apoptosis, showing the protective role of autophagy.ConclusionResults from the present study suggest that autophagy is an important and shared mechanism in other conditions related to inflammation or alterations of the immune system, such as periodontitis.

Oxidative Stress Correlates with Headache Symptoms in Fibromyalgia: Coenzyme Q10 Effect on Clinical Improvement

Background Fibromyalgia (FM) is a chronic pain syndrome with unknown etiology and a wide spectrum of symptoms such as allodynia, debilitating fatigue, joint stiffness and migraine. Recent studies have shown some evidences demonstrating that oxidative stress is associated to clinical symptoms in FM of fibromyalgia. We examined oxidative stress and bioenergetic status in blood mononuclear cells (BMCs) and its association to headache symptoms in FM patients. The effects of oral coenzyme Q10 (CoQ10) supplementation on biochemical markers and clinical improvement were also evaluated. Methods We studied 20 FM patients and 15 healthy controls. Clinical parameters were evaluated using the Fibromyalgia Impact Questionnaire (FIQ), visual analogues scales (VAS), and the Headache Impact Test (HIT-6). Oxidative stress was determined by measuring CoQ10, catalase and lipid peroxidation (LPO) levels in BMCs. Bioenergetic status was assessed by measuring ATP levels in BMCs. Results We found decreased CoQ10, catalase and ATP levels in BMCs from FM patients as compared to normal control (P<0.05 and P<0.001, respectively) We also found increased level of LPO in BMCs from FM patients as compared to normal control (P<0.001). Significant negative correlations between CoQ10 or catalase levels in BMCs and headache parameters were observed (r = −0.59, P<0.05; r = −0.68, P<0.05, respectively). Furthermore, LPO levels showed a significant positive correlation with HIT-6 (r = 0.33, P<0.05). Oral CoQ10 supplementation restored biochemical parameters and induced a significant improvement in clinical and headache symptoms (P<0.001). Discussion The results of this study suggest a role for mitochondrial dysfunction and oxidative stress in the headache symptoms associated with FM. CoQ10 supplementation should be examined in a larger placebo controlled trial as a possible treatment in FM.

Coenzyme Q10 Therapy

For a number of years, coenzyme Q10 (CoQ10) was known for its key role in mitochondrial bioenergetics; later studies demonstrated its presence in other subcellular fractions and in blood plasma, and extensively investigated its antioxidant role. These 2 functions constitute the basis for supporting the clinical use of CoQ10. Also, at the inner mitochondrial membrane level, CoQ10 is recognized as an obligatory cofactor for the function of uncoupling proteins and a modulator of the mitochondrial transition pore. Furthermore, recent data indicate that CoQ10 affects the expression of genes involved in human cell signaling, metabolism and transport, and some of the effects of CoQ10 supplementation may be due to this property. CoQ10 deficiencies are due to autosomal recessive mutations, mitochondrial diseases, aging-related oxidative stress and carcinogenesis processes, and also statin treatment. Many neurodegenerative disorders, diabetes, cancer, and muscular and cardiovascular diseases have been associated with low CoQ10 levels as well as different ataxias and encephalomyopathies. CoQ10 treatment does not cause serious adverse effects in humans and new formulations have been developed that increase CoQ10 absorption and tissue distribution. Oral administration of CoQ10 is a frequent antioxidant strategy in many diseases that may provide a significant symptomatic benefit.

Is inflammation a mitochondrial dysfunction-dependent event in fibromyalgia?

Fibromyalgia (FM) is a complex disorder that affects up to 5% of the general population worldwide. Both mitochondrial dysfunction and inflammation have been implicated in the pathophysiology of FM. We have investigated the possible relationship between mitochondrial dysfunction, oxidative stress, and inflammation in FM. We studied 30 women diagnosed with FM and 20 healthy women. Blood mononuclear cells (BMCs) from FM patients showed reduced level of coenzyme Q₁₀ (CoQ₁₀) and mtDNA contents and high level of mitochondrial reactive oxygen species (ROS) and serum tumor necrosis factor (TNF)-alpha and transcript levels. A significant negative correlation between CoQ₁₀ and TNF-alpha levels (r=-0.588; p<0.01), and a positive correlation between ROS and TNF-alpha levels (r=0.791; p<0.001) were observed accompanied by a significant correlation of visual analogical scale with serum TNF-alpha and transcript levels (r=0.4507; p<0.05 and r=0.7089; p<0.001, respectively). TNF-alpha release was observed in an in vitro (BMCs) and in vivo (mice) CoQ₁₀ deficiency model. Oral CoQ₁₀ supplementation restored biochemical parameters and induced a significant improvement in clinical symptoms (p<0.001). These results lead to the hypothesis that inflammation could be a mitochondrial dysfunction-dependent event implicated in the pathophysiology of FM in several patients indicating at mitochondria as a possible new therapeutic target.

Inmunohistochemical Profile of Solid Cell Nest of Thyroid Gland

It is widely held that solid cell nests (SCN) of the thyroid are ultimobranchial body remnants. SCNs are composed of main cells and C cells. It has been suggested that main cells might be pluripotent cells contributing to the histogenesis of C cells and follicular cells, as well as to the formation of certain thyroid tumors. The present study sought to analyze the immunohistochemical profile of SCN and to investigate the potential stem cell role of SCN main cells. Tissue sections from ten cases of nodular hyperplasia (non-tumor goiter) with SCNs were retrieved from the files of the Hospital Infanta Luisa (Seville, Spain). Parathormone (PTH), calcitonin (CT), thyroglobulin (TG), thyroid transcription factor (TTF-1), galectin 3 (GAL3), cytokeratin 19 (CK 19), p63, bcl-2, OCT4, and SALL4 expression were evaluated by immunohistochemistry. Patient clinical data were collected, and tissue sections were stained with hematoxylin–eosin for histological examination. Most cells stained negative for PTH, CT, TG, and TTF-1. Some cells staining positive for TTF-1 and CT required discussion. However, bcl-2, p63, GAL3, and CK 19 protein expression was detected in main cells. OCT4 protein expression was detected in only two cases, and SALL4 expression in none. Positive staining for bcl-2 and p63, and negative staining for PTH, CT, and TG in SCN main cells are both consistent with the widely accepted minimalist definition of stem cells, thus supporting the hypothesis that they may play a stem cell role in the thyroid gland, although further research will be required into stem cell markers. Furthermore, p63 and GAL-3 staining provides a much more sensitive means of detecting SCNs than staining for carcinoembryonic antigen, calcitonin, or other markers; this may help to distinguish SCNs from their mimics.

Can Coenzyme Q10 Improve Clinical and Molecular Parameters in Fibromyalgia

Fibromyalgia (FM) is a complex disorder that affects up to 5% of the general population worldwide. Its pathophysiological mechanisms are difficult to identify and current drug therapies demonstrate limited effectiveness. Both mitochondrial dysfunction and coenzyme Q10 (CoQ10) deficiency have been implicated in FM pathophysiology. We have investigated the effect of CoQ10 supplementation. We carried out a randomized, double-blind, placebo-controlled trial to evaluate clinical and gene expression effects of forty days of CoQ10 supplementation (300 mg/day) on 20 FM patients. This study was registered with controlled-trials.com (ISRCTN 21164124). An important clinical improvement was evident after CoQ10 versus placebo treatment showing a reduction of FIQ (p<0.001), and a most prominent reduction in pain (p<0.001), fatigue, and morning tiredness (p<0.01) subscales from FIQ. Furthermore, we observed an important reduction in the pain visual scale (p<0.01) and a reduction in tender points (p<0.01), including recovery of inflammation, antioxidant enzymes, mitochondrial biogenesis, and AMPK gene expression levels, associated with phosphorylation of the AMPK activity. These results lead to the hypothesis that CoQ10 have a potential therapeutic effect in FM, and indicate new potential molecular targets for the therapy of this disease. AMPK could be implicated in the pathophysiology of FM.